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Each year, hundreds of thousands of seals are clubbed and shot to death in Canada for their fur. This annual commercial seal hunt is the largest slaughter of marine mammals in the world. Join our ProtectSeals campaign in ending this cruel and needless killing for good.
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Great Seals Pinniped
Pinnipeds ("fin-feet",
lit. "winged feet") are
marine mammals belonging to the
former biological suborder Pinnipedia
(sometimes now a superfamily) of
the order Carnivora. The pinnipeds
now fall within the suborder Caniformia
and comprise the families Odobenidae
(walruses), Otariidae (sea lions,
eared seals, and fur seals), and
Phocidae (true seals). Recent molecular
analysis reveals that the closest
living relatives of the pinnipeds
are the bears, which was already
suspected for some time.[1] An alternative
hypothesis held that pinnipeds are
polyphyletic, with the true seals
derived from otterlike creatures
and the walruses and eared seals
from bearlike creatures, but the
aforementioned molecular study established
that the pinnipeds are indeed monophyletic
(derived from a common ancestor).
Pinnipeds apparently evolved from
a bearlike ancestor about 23 million
years ago, at the transition between
the warmer Paleogene period and
the cooler Neogene period. First
true seals and then walruses branched
off, forming new families.
Aquatic carnivorous mammal of the
families Otariidae and Phocidae (sometimes
placed in a separate order, the Pinnipedia).
The eared seals or sea lions (Otariidae)
have small external ears, unlike the
true seals (Phocidae). Seals have
a streamlined body with thick blubber
for insulation, and front and hind
flippers. They are able to close their
nostrils as they dive, and obtain
oxygen from their blood supply while
under water. They feed on fish, squid,
or crustaceans, and are commonly found
in Arctic and Antarctic seas, but
also in Mediterranean, Caribbean,
and Hawaiian waters.
In true seals, the hind flippers
provide the thrust for swimming,
but they cannot be brought under
the body for walking on land. Among
eared seals (and walruses), the
front flippers are the most important
for swimming and the hind flippers
can be brought forward under the
body for walking.
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Terminology
A group of seals is called a herd. A breeding
colony is known as a rookery. The young are
called pups; a group of pups is called a pod;
adult males are bulls, while females are cows.
True seals include the common or harbour seal
Phoca vitulina, found in coastal regions over
much of the northern hemisphere, with the largest
concentration around the Wash, in East Anglia,
England. The males may weigh twice as much as
the females. They feed on fish and squid. The
grey seal Halichoerus grypus, which grows to
2.7 m/9 ft, also has its main population around
British coasts, but occurs off the Canadian
coasts of Newfoundland, and around Iceland and
Scandinavia as well. In 1997 there were approximately
220,000 grey seals in the world.
The largest seal is the southern elephant seal
Mirounga leonina, which can be 6 m/20 ft long
and weigh 4 tonnes. The male has an inflatable
snout (an enlargement of the nasal cavity), which
acts as a resonator to amplify its cries. It feeds
mainly on squid, and spends 80% or more of its
life under water. Of its total population of 600,000,
half breed on the island of South Georgia. Elephant
seals are polygamous; pregnant females arrive
on the breeding ground and gather together, giving
birth in September; within three weeks they are
ready for mating again. In October a single male,
which can be three times larger than the female,
will claim a harem of as many as 100 females,
and will fight any other male that approaches
his territory, proclaiming his ownership with
a loud cry. Only fully mature males have the size
and strength to keep such a harem. After mating,
in November, the female produces a single pup,
which is suckled for several weeks without the
female leaving to feed, surviving on its blubber.
When the pup is weaned, the mother is ready to
mate again. Elephant seals travel 21,000 km/13,050
mi a year, between California's Channel Islands
and feeding grounds in the Pacific.
The smallest seal is the Baikal seal Pusa sibirica,
only 1.2 m/4 ft long and the only seal to live
entirely in fresh water.
Eared seals include sea lions and fur seals. The
rarest seals are the monk seals, the only species
to live in warmer waters. The Caribbean monk seal
Monachus tropicalis may already be extinct, and
the Mediterranean monk seal M. monachus, found
largely in the eastern Aegean Sea, and Hawaiian
monk seal M. schauinslandi are both endangered,
mainly owing to disturbance by humans. In 1996
the population of Mediterranean monk seals was
approximately 400–550. The population of
Hawaiian monk seals was around 1,200 in 1998.
The leopard seal Hydrurga leptonyx has distinctive
spotted markings on its underside, and is a fast-moving
predator of penguins, other species of seal, fish,
and krill. It eats penguins in a very distinctive
way, shaking the bird with its teeth to make the
flesh come off. Males grow to around 3 m/9.8 ft
long; females 3.5 m/11.5 ft. The pups are born
in November–January.
Despite their name, Crabeater seals Lobodon carcinophagus
do not eat crabs but krill, up to 20 kg/44 lb
each day, which they sieve from the sea with their
teeth. The most abundant of seal species, they
number between 15 and 30 million – more
than all the other seals put together; they are
the most abundant species of mammal after humans.
They never come to land, breeding on Antarctic
pack-ice. They live in small herds of fewer than
ten, and are monogamous. Their coat fades during
the year to white, until a fresh coat is produced
at the moult in January. At 2.5 m/8.2 ft long
and weighing 225 kg/496 lb, the females tend to
be larger than the males.
The Antarctic or Kerguelen fur seal Arctocephalus
gazella feeds mainly on krill. The male, at 150
kg/330 lb, weighs up to three times more than
the female. Like all fur seals, they have a double
coat of long guard hair covering a finer insulating
layer; to some extent, this fur replaces the thick
layer of blubber found in true seals. Like the
elephant seal, they breed in harems, with each
bull controlling five or ten cows. The pups are
fed by the cows for 117 days, the cow returning
to feed the pup every few days. Like other fur
seals, the Antarctic fur seal was almost wiped
out during the late 19th century by sealing expeditions.
It remained extremely rare until the 1950s, but
today has risen to 1.5 million. Most of the population
breeds on the island of South Georgia.
The Weddell seal Leptonychotes weddelli is easily
recognizable from its patterned coat with grey
and black flecks. These seals are the most southerly-living
mammals in the world, remaining during the winter
under the fast ice that never breaks up. They
achieve this by creating and enlarging holes in
the ice with their teeth; however, this results
in tooth decay and probably is the cause of their
short lifespan of around 10–15 years. They
grow to a length of 3 m/10 ft, and weigh 450 kg/990
lb; the females tend to be slightly larger than
the males. Each hole in the ice is the preserve
of one male, with several females using the hole
and mating with the male. Their diet consists
mainly of Antarctic cod, which they catch during
dives of up to 400 m/1,300 ft deep.
The Ross seal Ommatophoca rossi is the least known
of all the seals. It lives in deep pack ice and
is very rarely seen. It is thought to feed on
squid.
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